The present invention relates to strip or web feeding systems. In particular, the present invention relates to strip or web feeding systems for advancing of a strip of photographic material (i.e. film or print paper) in a photographic system.
In the photographic processing business, there is need for strip or web feeding systems which advance photographic film for photographic print paper by accurate distances. Photographic equipment which require these strip feeding systems include photographic printers, photographic film cutters, photographic film notchers, and phtotgraphic paper cutters.
In general, there are three types of strip feeding systems which may be used in a photographic system: manual, automatic, and semiautomatic. In manual systems, the entire movement of the strip is accomplished by the operator. Each strip feed is accomplished by the operator moving the film either directly or through some form of mechanical linkage.
Automatic strip feed systems typically include sensors which sense indicia on the film or paper which indicate a desire operating point or stopping point for the strip. Since no operator movement or positioning of the strip is required, the automatic feed systems are much faster and more efficient than a manual system.
Semiautomatic systems provide an alternative to the manual systems in those cases where the photographic strip material does not have indicia. Semiautomatic film and paper cutters, semiautomatic film notchers, and semiautomatic film needs for photographic printers have been developed. These systems provide higher speed operation than the manual strip feed systems, less complex and less expensive than automatic systems, and are capable of handling strips with no indicia.
In general, semiautomatic feed control systems have in the past used a moveable cursor or pointer to indicate the location of the next desired cut, notch, or location for printing. Examples of semiautomatic systems have movable cursors include Schwardt U.S. Pat. No. 3,315,862; Erickson U.S. Pat. No. 3,656,673; Tall U.S. Pat. No. 4,029,250; and a co-pending patent application by G. Strunc and W. Osby, Ser. No. 791,704 filed Apr. 28, 1977, and assigned to the same assignee as the present application.
In some cases, however, the moveable cursor-type control is disadvantageous. First, the moveable cursor system must include mechanical/electrical components which take up space in the equipment. In some photographic equipment, space considerations prevent the addition of a movable cursor-type system. Second, the movable cursor system requires extra moving parts.